Visceral adiposity is associated with altered myocardial glucose uptake measured by ¹⁸FDG-PET in 346 subjects with normal glucose tolerance, prediabetes, and type 2 diabetes

Background: The heart requires constant sources of energy mostly from free fatty acids (FFA) and glucose. The alteration in myocardial substrate metabolism occurs in the heart of diabetic patients, but its specific association with other metabolic variables remains unclear. We aimed to evaluate glucose uptake in hearts of subjects with normal glucose tolerance (NGT), prediabetes, and type 2 diabetes mellitus (T2DM) using [¹⁸F]-fluorodeoxyglucose-positron emission tomography (¹⁸FDG-PET) in association with visceral and subcutaneous adiposity, and metabolic laboratory parameters. Methods: A total of 346 individuals (NGT, n=76; prediabetes, n=208; T2DM, n=62) in a health promotion center of a tertiary hospital were enrolled. The fasting myocardial glucose uptake, and visceral and subcutaneous fat areas were evaluated using ¹⁸FDG-PET and abdominal computed tomography, respectively. Results: Myocardial glucose uptake was significantly decreased in subjects with T2DM compared to the NGT or prediabetes groups (p for trend=0.001). Multivariate linear regression analyses revealed that visceral fat area (β=-0.22, p=0.018), fasting FFA (β=-0.39, p<0.001), and uric acid levels (β=-0.21, p=0.007) were independent determinants of myocardial glucose uptake. Multiple logistic analyses demonstrated that decreased myocardial glucose uptake (OR 2.32; 95% CI 1.02-5.29, p=0.045) and visceral fat area (OR 1.02, 95% CI 1.01-1.03, p=0.018) were associated with T2DM. Conclusions: Our findings indicate visceral adiposity is strongly associated with the alteration of myocardial glucose uptake evaluated by ¹⁸FDG-PET, and its association further relates to T2DM.